[gmx-users] GPU considerations for GROMACS

[hairul.ikmal at gmail.com]

Hello,

Previously, I have helped building a workstation for my fellow
researcher who heavily uses GROMACS for his MD simulations, with the
following base specs:

-CPU: 8 cores (Xeon E2278G)
-RAM: 32GB
-GPU: 1x RTX2080Ti


With this setup, he managed to shrink down each simulation runtime to,
say approximately 12 hours, compared to previous system (purely CPU
only, no GPU support), which took days to complete.


1) Based on the current progress, we plan to build another system
(which will also run GROMACS most of the time) using the existing
workstation as reference. But currently we are unsure which setup
(Option 1 vs Option 2) will GENERALLY give shortest/fastest runtime,
when running the same set of GROMACS simulation :


Option 1:
Retain same CPU, RAM and GPU specs (1x RTX2080Ti)


Option 2:
Retain same CPU and RAM specs, but GPU wise, use 2x RTX 2070S instead
of 1x RTX2080Ti


2) Besides building another system, we are considering to upgrade the
existing system, too. For example, assuming the system has the
expansion capability (enough PCI-e 16x slots, power supply), will
adding another card (making it 2x RTX2080Ti instead of 1x RTX2080Ti)
into existing setup will significantly cut down current runtime?  If
yes, by how much time reduction can we expect generally with this
upgrade?


Appreciate if someone can share their thoughts and experience.
Thank you!


-Hairul